Library of the Olympic Studies Centre in Switzerland. The digital collections include official publications, journals, and selected dissertations. Some of the journals require a subscription for access; you can check to see if you have access through UNC's library.
The IOC is the non-governmental organization that organizes the Olympic Games. Its website includes highlights and official reports from past Olympics as well as documentation on funding, licensing, and other logistics.
Selected papers of the South African Non-Racial Olympic Committee, which was formed in South Africa in 1962 and led the international sports boycott of apartheid South Africa.
Annual reports from Freedom House, a non-governmental organization dedicated to research on democracy, civil liberties, freedom, and human rights. Link is to current report, but earlier years are available.